Air India Flight to Gatwick crash - unconfirmed 242 on board

Looks like they've found one of the black boxes already, so that will probably already be on a plane to the US to figure out what the issue was. They'll probably have a good idea within a week.
 
John67 said:
I have to say that, for the last few years, I try to book flights via airlines that use Airbus after the 737 tragedies.
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OK, but that was a specific problem with a specific, updated and redesigned model of the 737 (the 737 Max 8) that was identified and fixed. None of the other 737 models were affected, nor any of the other, differently-numbered Boeing planes.

It's true there have been a few other problems with Boeing aircraft recently, but nothing leading to hull loss while airborne.

And so far, there's no indication that this tragic and horrific accident was due to an aircraft design or manufacturing fault.
 
Nero80 said:
Yea i was on the understanding if the plane isnt correctly configured for take off or landing then an audible alarm sounds
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Actually, it would trigger multiple visible and audible alarms. Also, the crew would have to manually override several pre-flight configuration checks and warnings to even be able to start the takeoff run with the flaps in the wrong position.
 
Liamo said:
Preliminary report shows both fuel control switches were moved to the cut-off position shortly after take-off.

Fuel switches cut off before Air India crash that killed 260, preliminary report says

Various aviation experts are pointing out that it would be almost impossible to do this accidentally.
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It sounds like what information has been included in the preliminary report has been carefully considered, with some information deliberately withheld.

It's a strange explanation and no offers indication whether it was pilot error of mechanical failure.
 
ForssAwakens said:
There was a finding in 2017 about the locking feature disengaging, it was just an advisory (meaning nothing was required by airlines) and is in the report
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Well, almost. It didn't talk about the locking mechanism actually disengaging, only that it might potentially disengage, based on some reports of it not having been installed correctly on 737 aircraft, and advised (but didn't mandate) that these switches be inspected.

It also mentioned that the fuel control switches on other aircraft like the 787 were similar and so it suggested these could be inspected also.

I think this advisory bulletin has been way overplayed by some on the internet, in relation to this crash.

Firstly, there were no reports of the switches being installed incorrectly on any of these other models, only on 737's.

Secondly, there's never been a case of a fuel control switch on a 737 (even those that were incorrectly installed) or on any other model, moving by itself from the run to the cutoff position during flight, let alone two of them doing it within a second of each other.
 
Liamo said:
Preliminary report shows both fuel control switches were moved to the cut-off position shortly after take-off.

Fuel switches cut off before Air India crash that killed 260, preliminary report says

Various aviation experts are pointing out that it would be almost impossible to do this accidentally.
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Yeah, this is very odd.

Apparently on the CVR (Cockpit voice recorder), one of them said "why did you do the cut off" and the other one said "I didn't".

Some weird reports here, some say the switches were found in the off position, and some say they were cycled off and back on. They must have been back on, as the engines had started to spool up again, and one of them was already producing thrust when it crashed.
I don't care what the reports say, when they say "it's almost impossible to move both switches at the same time", if they did have the detent fitted, this is a myth. When you're flicking these switches every day (and there are loads like this) you get really good at overriding features like this one handed, without even thinking about it, if they're close together. Whether these detents were fitted or not doesn't really make a difference to whether it was one handed or two handed, can be done either way. Obv operating two switches with two hands is really obvious and the other pilot would ask questions. You could flick one after the other one handed too, which would be less noticeable, but as soon as you flick that switch the fuel cuts immediately and within a couple of seconds you would get all sorts of warnings as well as notice the sound changes.

If the detents were fitted though, then it would be tough to flick those switches to off by accident, as in moving your hand near there (not flicking the wrong switch). It's not like they would have throttled back (closest thing to the switches) and accidently flicked them off doing that, or moved the flaps back again (also close). The flaps will have already been set, pulled back a bit (and later pushed forward) and the throttles pushed forward where they stay. There's no real reason to be operating anything in that area so soon after take off, so accidental turn off by knocking it with something seems unlikely to me.

My best guesses are (in order of likelihood)
1 - One of them has flicked both switches by accident, when they've gone to change something else which has a detent, maybe the landing gear lever, and they've not even known they've done it. It was a pretty early flight, they could have been tired etc.
2 - Something has caught on or knocked both switches and flicked them both at the same time, this is possible and much more likely without the detent
3 - One of them has had a melt down and switched them off intentionally, but this seems unlikely as the pilots were doing maydays and trying to get them going again (maybe the one who said, "I didn't" just had a bit or regret/ didn't want to admit it?).
4 - Some sort of mad electrical fault has moved the switch on it's own, some switches can do this, but I don't think these can
5 - Someone else flicked the switches? Was anyone else in the cockpit who shouldn't have been there?
 
Andy_W said:
Yeah, this is very odd.

Apparently on the CVR (Cockpit voice recorder), one of them said "why did you do the cut off" and the other one said "I didn't".

Some weird reports here, some say the switches were found in the off position, and some say they were cycled off and back on. They must have been back on, as the engines had started to spool up again, and one of them was already producing thrust when it crashed.
I don't care what the reports say, when they say "it's almost impossible to move both switches at the same time", if they did have the detent fitted, this is a myth. When you're flicking these switches every day (and there are loads like this) you get really good at overriding features like this one handed, without even thinking about it, if they're close together. Whether these detents were fitted or not doesn't really make a difference to whether it was one handed or two handed, can be done either way. Obv operating two switches with two hands is really obvious and the other pilot would ask questions. You could flick one after the other one handed too, which would be less noticeable, but as soon as you flick that switch the fuel cuts immediately and within a couple of seconds you would get all sorts of warnings as well as notice the sound changes.

If the detents were fitted though, then it would be tough to flick those switches to off by accident, as in moving your hand near there (not flicking the wrong switch). It's not like they would have throttled back (closest thing to the switches) and accidently flicked them off doing that, or moved the flaps back again (also close). The flaps will have already been set, pulled back a bit (and later pushed forward) and the throttles pushed forward where they stay. There's no real reason to be operating anything in that area so soon after take off, so accidental turn off by knocking it with something seems unlikely to me.

My best guesses are (in order of likelihood)
1 - One of them has flicked both switches by accident, when they've gone to change something else which has a detent, maybe the landing gear lever, and they've not even known they've done it. It was a pretty early flight, they could have been tired etc.
2 - Something has caught on or knocked both switches and flicked them both at the same time, this is possible and much more likely without the detent
3 - One of them has had a melt down and switched them off intentionally, but this seems unlikely as the pilots were doing maydays and trying to get them going again (maybe the one who said, "I didn't" just had a bit or regret/ didn't want to admit it?).
4 - Some sort of mad electrical fault has moved the switch on it's own, some switches can do this, but I don't think these can
5 - Someone else flicked the switches? Was anyone else in the cockpit who shouldn't have been there?
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They are not switches you just 'flick' on and off like a light switch. There are guards against accidental flicking.

There is a metal guard either side of these switches to protect against accidental hand movements

There is a locking mechanism to these switches. You have to pull them up first to disengage the lock and only when you have pulled up can you move it to on or cut.

An electrical fault wouldn't override a physical manual pull operation before the switch can be moved to on or cut.

Another person would not be able to tamper with these switches without pilot or co pilot knowing as right between them...and as mentioned above they take effort to change. For the plane to take off the switches must have been on to get enough thrust to get airborne and then changed just after take off.

Accidental movement isn't impossible but its highly unlikely.
 
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Jonny Ingbar said:
It's a strange explanation and no offers indication whether it was pilot error of mechanical failure.
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Really? There's no hint of any mechanical failure, or anything that would have caused the switches to move by themselves. I think it's implicit in the report that one or other of the pilots moved the switches.

The Special Airworthiness Information Bulletin referred to in the report, of an issue that has been reported in 737's, could theoretically have led to a situation where the switches were not locked in place and so could have become easier to move by accident but again, for that to happen on a 787 where it has never been reported and with both switches - not simultaneously, but one after another with a slight delay in between, seems highly unlikely.
 
Liamo said:
Really? There's no hint of any mechanical failure, or anything that would have caused the switches to move by themselves. I think it's implicit in the report that one or other of the pilots moved the switches.

The Special Airworthiness Information Bulletin referred to in the report, of an issue that has been reported in 737's, could theoretically have led to a situation where the switches were not locked in place and so could have become easier to move by accident but again, for that to happen on a 787 where it has never been reported and with both switches - not simultaneously, but one after another with a slight delay in between, seems highly unlikely.
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The guards either side mean you have to deliberately move your hand into the right position to initiate the unlock uplift pre switch change.

In other words...to change the settings on these switches...you know what you are changing...as it takes sufficient effort to do so.
 
Liamo said:
Well, almost. It didn't talk about the locking mechanism actually disengaging, only that it might potentially disengage, based on some reports of it not having been installed correctly on 737 aircraft, and advised (but didn't mandate) that these switches be inspected.

It also mentioned that the fuel control switches on other aircraft like the 787 were similar and so it suggested these could be inspected also.

I think this advisory bulletin has been way overplayed by some on the internet, in relation to this crash.

Firstly, there were no reports of the switches being installed incorrectly on any of these other models, only on 737's.

Secondly, there's never been a case of a fuel control switch on a 737 (even those that were incorrectly installed) or on any other model, moving by itself from the run to the cutoff position during flight, let alone two of them doing it within a second of each other.
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i was only stating what was reported on bbc and giving a high level overview not a technical one . I haven’t listened to the internet (although I have watched pilot blog video after posting)

The 737 and 787 are almost identical and therefore that is why it was included in the report.

it was that it was installed with locking disengaged, and that element can be replaced therefore potentially a new installation for it to be disengaged, and is relevant to this craft as had 2 replacements previously

That said due to the 1 second gap between them suggest it was engaged and human would have to do this
 
Liamo said:
Really? There's no hint of any mechanical failure, or anything that would have caused the switches to move by themselves. I think it's implicit in the report that one or other of the pilots moved the switches.

The Special Airworthiness Information Bulletin referred to in the report, of an issue that has been reported in 737's, could theoretically have led to a situation where the switches were not locked in place and so could have become easier to move by accident but again, for that to happen on a 787 where it has never been reported and with both switches - not simultaneously, but one after another with a slight delay in between, seems highly unlikely.
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The report is ambiguous and has been criticised in being so, as it hasn’t attributed the error to human or mechanical failure

You think they would be able to identify from the voice recording which pilot said what as well but they haven’t said which one said ‘why did you cutoff’ and the one who said ‘I haven’t’

It’s feels to me the person who said ‘why did you cutoff’ would be more likely, but it’s plausible for either

Also it your hands got throttle control what would that mean for the guards, does it make easier/harder
 
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SydneyRed said:
They are not switches you just 'flick' on and off like a light switch. There are guards against accidental flicking.

There is a metal guard either side of these switches to protect against accidental hand movements

There is a locking mechanism to these switches. You have to pull them up first to disengage the lock and only when you have pulled up can you move it to on or cut.

An electrical fault wouldn't override a physical manual pull operation before the switch can be moved to on or cut.

Another person would not be able to tamper with these switches without pilot or co pilot knowing as right between them...and as mentioned above they take effort to change. For the plane to take off the switches must have been on to get enough thrust to get airborne and then changed just after take off.

Accidental movement isn't impossible but its highly unlikely.
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I know how they work, I've operated these switches with the detents and without thousands of times. I was an aircraft engineer (Avionics), operating, testing and replacing these switches/ control units etc was part of my trade.

The guards look more like side shields, and doesn't look like it would do much, it's not like a weapons release or a crash switch or whatever which has an actual cover.

Some of the questions where whether they had the detents or not, but yeah, inadvertent operation is unlikely with the detents but still not impossible, I've seen it done! People have pulled ejection seat handles by accident.

Yes, they're mechanical switches, but some aircraft have the ability to move mechanical switches (I don't think this does for these switches, which is why I said so). I can't think of any which move switches with detents (but it's been a while).

Of course another person operating the switches without the pilots realising is highly unlikely, but they are in the centre console, to the side of the pilot and copilot, they could be out of vision. They throttles are around where a gear stick is on a car, and the switches rearward of that. Can you see the gear stick when you're looking out the front window?

If someone was low they could maybe get at them, but yeah exceptionally unlikely, would be awkward ot do with the detents from that angle though. Obviously if the cockpit is locked and there's nobody else in there then it's impossible. There are other seats in the Dreamliner cockpit though, behind the pilot, inside the locked door. If there's a time where those switches could get flicked without either noticing, then it's on takeoff (or landing).
 
Was it confirmed that there were only two pilots onboard ? I thought a flight over that duration would have required three of them?
 
The report said there was only a second between switches cut off though. To do this intentionally and manually it would surely take more than 1 second? Obviously I am no expert, but the time difference to me suggests a computer or electrical cause rather than manual but like I say other than watching ‘Air-crash Investigates’ I have no insight.
 
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